Bag opening and filling machine



H. G. ALLEN 2,272,258

BAG OPENING AND FILLING MACHINE Feb. 10, 1942.

Filed Nov. 4, 1938 v11 shee'ssheet '1 FIGA.

ATTORNEY Feb. 1o, 1942.' H. G.. ALLEN 4:2,272,258

BAG OPENING AND FILLING MACHINE Filed Nov. 4, 19:58 I1 sheets-sheet 2 INVENTOR Feb. 1'0, 1942.

H. G. ALLEN BAG OPENING ANDFILLING MACHINE l1l Sheets-Sheet 5 Filed NOV. 4, 1958 INVENToR HOM/PD G. ALLE/V ATTO R N EY Feb. 10, '1942. H. G. ALLEN 2,272,253

BAG OPENING AND FILLING MACHINE Filed Nov. 4, 1958 11 sheets-sheet 4 INVENTOR ATTORNEY m n.. A a m A M H FIG, 4.

H. G. ALLEN BAG OPENING AND FI'LLING MACHINE Feb. 1o, 1942.

11 sheefs-sheet 5 Filed Nov. 4, ,1958

Feb. 10, 1942. H. G. ALLEN 2,272,258

BAG OPENING AND FILLING MACHINE Filed Nov. 4, 1938 l1 Sl'lee-ts-Sheefl 6 mafia lNvENTOR HOWARD GAME/V ATTORN EY Feb. 10, 1942.

H. G. ALLEN BAG OPENING AND FILLING MACHINE 11 Sheets-Sheet '7 Filed NOV. 4, 1938 FIG. 11.

m` u RA ma D WM mw t ATTORNEY AFeb. 10,/1942. H. G. ALLEN 2,272,258

BAG OPENING AND FILLING MACHINE Fi1ed Nov. 4, 1958 11 sheets-'sheet 8 INVENTO R l HOWARD G. ALLE/V 5 B,

ATTO RIN EY Feb. 10, 1942. H G ALLEN 25272,258

BAG OPENING AND FILLING MACHINE Filed Nov. 4, 1958' 11, sheets-sheet 9 FIG. IZ

4 wif/ fz? o -264' l l l l lNvx-:NTOR m \43 A How/wo a ALLE/v ATTORNEY Feb. 10, 1942.

H. G. ALLEN BAG OPENING AND FILLING MACHINE 1l Sheets-Sheet l0 Filed Nov. 4, 195s INVENTOR ATTO m L A Y e m R w l y W 1,5, H M.

Feb. 10, 1942. H. G. ALLEN BAG OPENING AND FILLING MACHINE 1l Sheets-Sheet ll F1625 H622 FIG wllGpl H623 N Irl-G27- f Patented Feb. 1o, 1942 BAG OPENING AND MACHINE Howard G. Allen, North Tonawanda, N. Y., as-

sig'nor to Consolidated Packaging Machinery Corporation, Buffalo, N. Y.; a corporation of New York Applieation November 4, 193s, serial No. 238,771

18 Claims. (Cl. 226-59) My present invention relates to a bag-opening device, 1-

'I'he yinvention is particularly concerned with the provision of a bag-opening device which is adapted to open and shape paper bags of any ofthe well-known types. The invention further contemplates the provisionof means for'filling a bag after the same has been opened and.

shaped. Particular advantage is derived by my invention in that it is not limited to any particular type of paper bag and in that it will open and shape paper bags of'types which have heretofore been limited to hand-opening and shaping.

yIn the packaging of granular or pulverulent materials, such as sugar, coffee, cocoa orilour, it is highly desirable to employ a paper bag for reasons of economy. From ay mechandising standpoint, commodities must be packaged in an operation of folding one end upon itself and pasting the folded end lto'an outer wall of the bag body. In some instances; score lines may be formed in proper spaced relation to the closed end to assist in the definition of a square bottom,- but such score lines do not serve to preform or otherwise establish an. easily squared bottom. In order to meet merchandising requirements in the packaging of sugar; coffee and the like, the square bag must be opened and its bottom must be completely squared by deliberate manipulation prior to the introduction of the commodity therein.

Other forms4 cfu-bags whose bottoms are not preformed and which musttherefore be openedA and squared prior to flllinginclude those whosebottoms are closed by stitching and/or tape and which may or may not have gussets formed thereattractive and easily handled manner. For this reason,` the economies effected by paper bags have been foregone in manyinstances because of the desirability of an attractive package. With this problem in mind,certain types of paper bags have been designed -with preformed bottoms which may be easily squared and shaped. Certain bags have been so designed that the mere insertion of material or the insertion of an air blast therein will square and shape the bottom. Bags of this type include those bags which are commonly 'referred to as automatic, -ABC, selfopening, Satchel bottom or diamond fold.

Other types of bags do not lend themselves to such easy opening and shaping because the bot-- coffee or similar commodities are to be packaged in bags of these types, the bottoms must be squared in order thatthe resultant package will be capable of standing on its own bottom and in order that the merchandising requirements shall be met.

One particular form of bag'of the type discussed in the preceding paragraph is commonly known as the square bag. This bag. consists of a gusseted flattened tube cut to desired size.

The bottom of this bag is nosed by the simplest Fig. 4;

in as well as non-gusseted envelopes of various types.

It is an object of the vpresent invention to provide a machine which will .open and shape bags of any of the types discussed above.

It is a further object of the present invention to provide a machine which will open and square the bottoms o-f bags of those types whose bottoms must be squared prior to filling.

Itis a further object of this invention to provide means for automatically lling vbags which have been opened in accordance with the objects above stated. f

Other and further objects of this invention will become more'apparent from a considerationof the following description of a preferred but not necessarily`the only form of the invention taken in connection with the drawings accompanying and v forming a part of this specification.

In 'the drawings:

Fig. 1 is a front elevation of a machine constructed according to the present invention;

Fig. 2 is an enlarged detail view of a part of I the machine shown in Fig. 1 with the valve-box cover removed;

Fig.- 3 is a section along the line 3-3 of Fig. 2; Fig. 4 is a section along the line 4-4 of Fig. 2; Fig. 5 is a section along the line 5-5 of Fig. 3; Fig. 6 is a section along theline 6--6 of Fig. 2

showing the .bag-opening carriage in its operbag in position Fig. 11 is a section along the line II--II oi Fig. 9 with the opened bag in section to expose the opening fingers to View;

Fig. 12 is a detailed'elevation of a rear hinge member having a rear-opening nger attached thereto;

Fig. 13 is a section along the line Iii-I3 of Fie. 9;

Fig. 14 is a section along the line ifi-I4 of Fig. 13;

Fig. 15 is a section along the line I5--i5 of Fig. 2, and for clarity of illustration the hopper II has been omitted and the spout I has been sectioned below the plane of line i-l;

Fig. 16 is a rear elevation of the valve box and supporting means therefor taken in the plane in dicated by line Iii-i6 of Fig. 15;

Fig. 1? is a section along the line li--Il of Fig.

Fig. 18 is a section along the line ill-I3 of Fig. 15;

Fig. 19 is a section along thevline Iiii9 of Fie. 15: Fig. 20 is an enlarged view similar to Fig. 16 and showing valve ports and valve seat passage Ways in dotted lines;

Figs. 21, 22, 23, 25, 26 and 27 are diagrammatic views showing the operation of my device in opening and shaping a square bag; and

Fig. 24 is a section along the line 24-24 in Fig. 27.

Each of the sectional views above identified has been taken in the direction indicated by the arrows accompanying the .respective section lines. I

Similar characters of reference indicate similar parts throughout the several views.

Referring now to the drawings, there is shown a machine constructed according to my invention. In general, this machine comprises a pedestal or standard I0 upon which is supported a lling hopper II and a bag opening device in- Y dicated generally at I2. A magazine I3 is provided to hold a supply of bags I4 in a position accessible to the operator. A continuously driven conveyor I5 is supported with the magazine I3 upon a frame supported by the pedestal I0 and additional pedestals I6 and II. Amotor I8 is supported upon the frame and serves to drive the conveyor I5 as well as other parts of the D machine to be more particularly described hereinafter. The frame further supports adjustable bag guides I9 and 20 which serve to guide filled bags in their travel upon the conveyor I5.

. ported above the lling. hopper Il. The cam shaft 34 controls the weighing and dumping mechanism within a battery of automatic weighing and dumping devices 35 supported above the hopper II. 'I'he weighing devices 35 are supplied with the commodity to be packaged by individual spouts 36 leading vfrom a suitable source of supply. The material to be packaged is conducted by gravity or otherwise through the spouts 3B to the automatic weighing devices 35 which are arranged to operate in definite order under the influence of the cam shaft 34. As shown in the drawings, there are four weighing devices 35 which operate successively in order to give ample time for accurate weighing of successive charges of material to be packaged. The details of the weighing and dumping apparatus form no part of the present inventionand it is to be noted that any such apparatus may be used wherein the dumping operation may beaccurately controlled. For thepurposes of the present invention it is sufficient that the weighing devices shall furnish weighed charges of material to the hopper II indefinite timed relationship with the operation 'of the bagopening device in order that a charge of material may be introduced into a bag immediately thatlthe same has been opened and shaped to receive such material. 4

The cyclic rate of operation of the bag opening device and of the weighing land filling devices may be varied by changing tl'ie speed of the motor I8 or by variation in gear ratios within the gear box 24.

In the operation of the device thus generally described, a b ag 31 is transferred from the stack I4 to a suitable gripping device forming a part of the bag opener. The transfer of the bag from the stack I4 to the baggopener may conveniently be manually effectedil However, it is to be distinctly understood that such transfer may be made by suitable automatic devices. 'I'he gripping device holds the bag in position while the opening device opens and squares the bottom The opening mechanism is preferably cyclically operated by fluid pressure under the control of the motor I8. To this end, the motor I8 drives, through a belt 2| and pulley 22, a shaft 23 which enters a gear or reduction box 24' containing suit able gearing for driving the conveyor l5 and a shaft 24 at a desirable speed. The shaft 2d is supported in a suitable bearing 25 upon the frame and carries a sprocket 26 which through a suitavble sprocket chain 21 and sprocket Wheel 28 imsprocket wheel 33, drives acam shaft 2l sup- '"5 of the bag 3l. When opening and squaring is complete, a charge of material is placed into the bag by the filling device. Immediately thereafter, the bag is released by the gripping device, and dropped upon the conveyor I5 which, together with the guides I9 and 2, conducts the lled bag 31 to a delivery point.

The device thus generally described operates in fixed cycles and it is necessary that the empty bags shall be placed in position upon the opening device at a particular portion of the cycle. Oc-

casional failures to thus properly` position the bag must be expected and, accordingly, the conveyor I5 is preferably constructed of open material auch as coarse flexible wire mesh through which material discharged by the Weighing device maypass to a spillage bin 38 located directly beneath the discharge opening of the lling device.

For convenience in manual manipulation, the bag magazine I3 may comprise a trough-like body having a generally vertical front wall. A shelf 39 may be provided in such a position as to support the stacks of bagsI Il in an inclined relationship against the vertical front wall of the magazine. The upper edges of the bags will thus be'ofset relative to one another in order that the uppermost bag may be conveniently separated and removed from the stack. i

A detailed description of the bag opening and squarlng device will now be given. Referring first to Figs. and 16, there is shown a spaced pair of clamp blocks 40 which may be conveniently clamped to the standard IIJ by U-bolts 4I which pass through suitable recesses or openings in the clamps 40 and through angles 42 and 4-3 re-.

spectively. The opening and squaring device of the present invention is supported upon the angles 42 and 43. The construction thus described provides a firm and steady support and at the same time provides for vertical adjustment ofthe device relative to the standard l0. Such vertical adjustment may be availed of to .accommodate the device to be hereinafter described for operation upon bags of various sizes and types.

The angles 42 and 43 serve through suitable supporting means to support the valve box 30 and the bag opening device I2. It will be understood that the hopper Il and weighing devices 35 shown in Fig. l are supported -by the standard I8 by suitable means not shown.

mensons supported in fixed relationship with` the bag opening frame and designed for cooperation with the bag opening fingers.

' 60 in which are formed suitable apertures for The bag opening device I2 comprises in geny tangularplanes of dimensions less than the rectangular dimensions of a bag when fully opened and may be easily introduced into a bag and to expand to such position as to define rectangular planes substantially equal in al1 dimensions to the rectangular outline of an opened Paper bag. These fingers are Asupported for vertical motion whereby they may be projected in their collapsed condition into the interior of aI bag and then expanded to bag-shaping position.

A complementary pair of angles 44 and 45 are suitably interconnected by members46 and 41 whichform parts of 'cylinder heads to be hereinafter described and a spacer or top covering member 48 to form a stationary frame upon which the principalelements of the bag-opening device are supported. This frame is supported in a vertical`position by the angles 42 and'v 43 as shown inFig. 2. The cover or spacing member 48 has suitably attached thereto or formed in- ;tegrally therewith a downwardly extending chanreception of fastening means such as screws 6| which secure the finger 54 to the hinge member 58. vThe web 60 has formed thereon a lip 62 (Fig. 10) which serves asl a seat for the angular corner of nger 54. A boss 63 is formed integrally with or otherwise secured to the outer face of the web 66 and serves to receive a bearing stud 64. The stud 64 has a reduced portion 65 passing through a mounting plate 66 and is secured to the mounting plate as by a nut or cap screw 61. The boss 63 abuts the mounting plate 66- and is held upon the stud 64 by a suitable retaining collar 68 (Fig. 4). The structure thus described provides for rocking movement of the hinge 58 and finger 54 about the stud 64 as an axis. A stud 69 (Fig. 13), similar to the stud 64, is provided as an axis for the hinge member 59 and finger 55 is mounted at the opposite end of plate 66. 'I'hese two studs are parallel and hence the front fingers 54 and 55 may be rocked toward and away from one another in a vertical plane parallel to the plane of the section upon which Fig. 13 is taken. v

As shown in Figs. 13 and 14, the 'front fingers 54 and 55 are interconnected by an angularly disposed link'lil pivoted at its ends to suitable pivot mountings 1| and 12 provided respectively upon'the fingers 54 and 55.l Theangularity of the'link 10 and the disposition of its pivots relanel-shaped extension comprising a rear wall 49 and side walls 50. The walls 49 and 58 may conveniently fit in telescoped relation upon the side walls of angles 44 and 45 and serve therewith to form a. generally rectangular enclosure for certain of the operating parts to be described.

At its lower end, the wall 49 has secured thereto by suitable means, such as rivets and spacing members, a spout 5l. The spout 5l (see Fig.-3) is designed to form a continuation ofthe hopper ii and to this end is supported in telescoping relationship with the lowermost end of the hopperil.

tive tothe studs 64 and 69 are such as to cause all angular movements of the fingers 54 and 55 about their axes 64 and 69 to be equal in extent Y members 58 and 59 has rearwardly and do,wn

As seen in Fig. 6, the spout 5| is of generallyl tapered conformation and diminishes in crosssection toward the lowermost end thereof. By

I' reference to Fig. 9 it will be seen that the spout l 5l is provided with angular indentations 52 formed in its rear comers and extending through the maior portion of the length of the spout.

These indentations are of suicient depth to'accommodate the thickness of the bag opening fingers in order that the fingers and the rear wall 58 of the spout may form a generally plane or flush surfacewhen the fingers are collapsed and in their uppermost position as shown in Fig. 4. Bythe construction thus defined there Ais provided a tapered spout of suitable length and diwardly projecting extensions 13 and 14. Each of these extensions carries a boss, one of which is indicated at 15 in Figs. 4 and 10 and the other at 16 in Fig. 11. These bosses are adapted to receive stub shafts 11 and 18 formed upon hinge members 19 and 88 which are provided for support of the .rear fingers 56 and 51 respectively. As particularly shown in Fig. 10, the boss 'i5 is confined between the body of the hinge and a retaining cap or ring '8| secured as by a cap screw 82 to the stub shaft 11. The axis of rotation of stub shaft 11 is disposed at approximately a right angle to the axis of rotation of the hinge 58 vabout the lstud 64 and these two axes are located generally within the same horizontal plane.

As a result, .the hinge 19 rocks withhinge 56 vits respective bag-opening iinger 56 or 51 as by screws 83 passing through a web portion 04 of the hinge and threadably received in the linger. Each of the hinge members is further provided with a nger-seating lip 85 similar to the lip R52 provided upon the front hinge members 55 and 55.

The ngers 54, 55 and 56, 51 are spring urged into their collapsed position as illustrated in Fig. 4. To this end, the hinge member 50 is provided with an upwardly extending, perforated ear 08 and the hinge member 59 is provided with. a similar ear 81. The perforations in the ears 85 and 81 are tapped to threadably receive set screws 88 and 89 respectively which are provided with suitable lock nuts 90 and 9| (Figs. 9 and 13) A rod 92 is provided with reduced end portions which are loosely positioned in the perforations of the ears 86 and B1. Mounted upon the rod 92 is a pair of spacing collars 93 and an expansible spring 94. The spring 94, acting through collars 93, tends to spread the upper ends of the hinges 58 and 59 apart and thus to swing the lower portions of the front-opening ngers 54 and 55 toward one another about the studs 04 and 69. The set screws 88 and 89 constitute adjustable stops to limit the swinging movement of the fingers in the opposite direction under the influence of means which lwill be hereinafter described. To this end, the screws 88 and 89 may be adjusted to abut the ends of rod 92 at various angular positions of the fingers.

As explained above, the rear iingers 56 and 51 swing toward and away from each other with the front fingers 54 and 55. The spring 94, therefore, influences the rear fingers along with the front. It is considered advisable to provide an additional expansiblespring 95 (Figs. 9 and 11) carried by a rod 95 whose ends are loosely received by sockets 91 and 98 mounted respectively upon the rear hinges 19 and 80. The ends of the spring 95 bear upon the sockets 91 and 98 and the expansive force of the spring 95 serves to assist the spring 94 in urging both sets of fingers into collapsed position,

Contractile springs 99, (Figs. 6 and 9) are anchored respectively to the rear hinges 19 and 80 and to a relatively iixed part of the bag opening frame. The springs 99 and |00 tend to rock the rear hinges 19 and 80 about the stub shafts 11 and 10 to swing the rear fingers inwardly toward the spout 5|.

The springs 94, 95 and 99, |00 tend to swing the rear fingers 55 and 51 into a position wherein they will closely nestwith the inwardly sloping rear corners of the spout 5| and the indentations 52 formed in the rear wall 53 of the spout. The springs 94 and 95 tend to swing the front fingers 54 and 55 into a position wherein they will closely nest with the substantially vertical front corners of the spout 5|. In Fig. 15, the spout 5| has been sectioned in a horizontal plane substantially below the plane of the line |5|5'in Fig. 2 in, order to illustrate the nested position of the fingers and spout when the fingers are collapsed and the'bag-opening carriage is in its uppermost position. When the'ngers are thus collapsed, the fingers and the spout 5| form a substantially smooth, tapered body which may be readily inserted into the mouth of a bag.

According to the present invention, suitable power actuated means is provided to rock the bag-opening ngers about their respective axes against the force of the springs 94, 95, 99 and |00 into a position wherein the fingers form a generally rectangular, skeleton-like form of shape and size conforming to the interior shape and size of a bag with which the device is to be used. In the embodiment shown in the drawings, the power means is actuated by a uid pressure medium such as compressed air although it is to be understood that any suitable uid pressure medium may be used or that suitable electrical or mechanical power actuated means may be substituted for the fluid pressure actuated means herein disclosed.

As shown in Fig. 15, there are provided two uid pressure motors |0| and |02 of the cylinder and piston type. These motors are connected by tubes |03 and |04 and a suitable iitting |05 to a tube |06 which is connected with the valve box 30. The valve mechanism within box 30 is so designed as to alternately direct air under pressure to the motors |0| and |02 and to allow the air in the motors to exhaust as will be explained in detail hereinafter.

In Fig. 6 the motor |02 is shown in section and it comprises a clamp ring |01 in which a cylinder |08 is seated, a cylinder head |09 and a piston ||0. The cylinder body is conned between the clamp ring |01 andthe cylinder head |09 by' bolts or cap screws passing through external portions of the head |09 and threadably received in the clamp ring |01 (Fig. 9). The piston La provided with a exible packing cup ||2 held thereon as by a washer I3 and cap screw H0. The head |09 'is provided with a port ||5 adapted to-receive a suitable iitting HB for connection with the tube |04. Air is admitted toand exhausted from the interior of the cylinder through the port I5.

The clamp ring |01 has lateral extensions loosely connected as by pins ||1 (Fig. 9) to a pair of rearwardly extending links H8 and ||9 pivotally connected at their forward ends, as at |20 and |2|, to suitable bifurcated ears |22 and |23 formed upon the front hinge members 58 and 59, respectively. The links I|8 and ||9 serve to hold the motor |02 in proper lateral positionrelative to the bag-opening device and the loosely pivoted construction provides the necessary freedom of movement of the front hinges 58 and 59.

The motor |02 is supported in a vertical direction by an angle |24 (Fig. 6) secured as by cap screws |25 to the clamp ring |01 and to a cross bar |26 (Figs. 6 and 1 1). The cross bar |26 is pivotally supported at its ends upon trunnlons |21 formed upon the rearward extensions 13 and 14 of front hinge members 58 and 59. The cross bar |26 may be held upon the trunnions |21 by any suitable means such as cotter pins |28 (Fig. I0). The trunnions |21 are so place'd upon their respective hinge extensions that their axes form a .continuation of the axes of studs 54 and 59 er steadiness and uniformity oi' operation.

The piston'HU has formed thereon a bifurcated portion |29 extending outwardly from the cylinder (Figs. 6 and 9) and drilled to receive a pin |30. A horizontally disposed push rod |3| is received within the bifurcation and is pivotally connected to the piston by the pin |30. The rear hinge members 1,9 vand 30 have formed thereon bifurcated rearward extensions |32 which receive Vrollers |33Jrotatably mounted upon pins |34 carried by the extensions |32 (see Fig. 12).I The rollers |33 are held against the push rod |3| by the springs 99, |00. When air is admitted to the motor |02 the piston 0 is'driven to the right as viewed in Figs. 4, 6 and 9 and the push rod |3| bears against the rollers |33 to rock the rearlngers 56 and 51 about their pivots 11,v 18 to move the fingers from the position in Fig. 4 to the position in Figs. 6 and 9. The pivotal mounting of push rod |3| acts to equalize the uniformity of operation. The anti-friction rollers |33 are provided to permit free swinging of the hinge members 58,' 59 and 19, 80 about the stud shafts 11 and 18 by meanswhich will hereinafter be described.

Adjustable stops are provided to accurately limit expansive movement of the rear fingers 56 and 51 under the influence of the fluid pressure motor |02. These stops may comprise screws |35 (Figa 4 and 9) threaded., through upward extensions |36 formed upon the front hinge members 58 and 59.. I'he rearward ends of screws `|35 extend into' positions to be abutted by the upper portions of the'rear hinge members 19 and 80. Suitable lock nuts |91A may be provided to hold the screws |35 in proper adjusted position.

'I'he uid pressure motor |0| may be identical with the motor |02 and detaileddescription thereof will be omitted. The clamp ring |38 ofthe motor has extensions :|39 formed thereon which` extensions are drilled to receive draw rods pressure exerted upon the lingers' and to insure 'geraete against the stop nuts |54 and the draw rods |40 andV |4| whereby the draw bar |44 is caused to rock the hinge members 59 and 80 abouttheirpivot 69 toward the position illustrated in Fig. 11. The ultimate position of the hinge members and fingers carried thereby under the inuence of motor |0| is adjustably limited by abutment of cross rod 92 with screws 88 and 89 as above described. The loose engagement of rod |40 with the apertures |42 in the front hinges and the loose engagement of the rod `|4| in the slots |43 in the rear hinges are provided to prevent binding due to relative angular movement between the hinge members and the draw rods. The slots |43 allow swinging movement of the rear hinges transversely of the draw rod |4|. 'I'he pivotal connection |41 between the piston of motor |0| and the y push bar |49 allows movement of various parts without danger of binding. The antifriction rollers |33 and |50 act as thrust members for cooperation with their respective push bars |3| and |48, and, at the same time, facilitatel the rela.- tively transverse movement between the rear hinge members and thrust bars which occurs as a result koi? the bi-planar swinging movement of t the rear hinge members. v

In Figs. 2, 4 and 6 there is shown a bag-holding device which is particularly adapted forv use position. The bag-holding device is supported at a level somewhat above the lower end of spout 5| in order that the mouth of a bag may be introduced overthe spout and heldy by the holding 40 and |4| which act as the sole support for the motor |0|. The rod |40 extends through enlarged openings |42 formed in each of the front hinge members 58. and 59 (Figs. 4 and 6) and extendsoutwardly. beyond the opposite side of the bag-opening carriage (Fig. 9),. The rod |4| extends through emerged, horizontally extending slots |43 formed in each of the rear hinges 19 and 80 (Figs. 4 and 6) and extends outwardly beyond the opposite side of the bag-opening carriage (Fig. 9). The outwardly extending ends of the rods |40 and |4| extend through a draw bar |44 held on the rods-as by nuts or caps |45 secured to the ends of rods |40 and |4|.

The piston of motor |0| has a bifurcated extension |46 to which is pivotally attached, as by a pin |4'|,'a push bar |48 drilled adjacent its ends for sliding reception of the rods |40 and |4| (Fig. 9). The push bar |48 is adapted to bear against a stud |49 extending laterally from the front device in position for opening, shaping andi-Illing as shown in. Figs. 2, 4 and 6.

As shown in Fig. 4, an angle |58 is supported between angles 44 and 45 and has a downwardly projecting portion |59l which carries a spacing block '|60 to which the clamping plate |51 is attached. The spacing block |60 has mounted face of plate |51 and the upper edge or lipof this wall may' be easily forced between the plate |51 and the spring pressed rollers |55. 'I'he tension Y ofsprings |63 is so chosen as to hold an empty hinge member 58 and an antifriction roller |50 rotatably mounted in a bifurcated lateral extension |5| of the rear hinge member 19 (see Fig. 12).

The draw bar |44 is adaptedto bear against a stud |52 and roller |53 carried respectively by- -the front hinge 59 and rear hinge 80 and respectively similar to the stud |49 and roller |50 above described. The draw rods |40 and |'4| extendA through which the motor may be 'supplied with bag in position but to be ineffective to hol/d a filled bag. v

Referring now to shaft |6| also carries a pair (Fig. 2) of bell crank levers |64 working in slots in the projection |59. The lower arms of .the bell cranks 64 carry a cross shaft |65 on which the clagmping jaw |56 is pivotally carried. The other, substantially horizontal arms of bell cranks |64 are pivotally connected as at |66 to a piston |61-of a uid pressure motor |68 similar in essential. features to the motors I0| and |02 described above. The motor |68 maybe conveniently supported within the angle |58 and is provided with va'port |69 air vunder'pressure and through which the motor may exhaust.- The port |69 ,has therein a suitable tting' |10 to which is connected a tube |1| Fig. 4, it'will be seen that the- 36. A tension spring |12 is stretched between A,

, the piston pin |66 and a suitable anchorage |13 on the motor body. The spring |12 serves to return the piston |61, bell cranks |64 and clamp |56 to open or non-clamping position-when the air is permitted to exhaust from motor |68.

'I'he clamp |56 serves to firmly hold a bag 31 iirposition while it is being opened, shaped and lled and is of such strength as to securely hold a filled bag. Thus,` an empty bag may be positioned upon the bag-holding device and held temporarily by the rollers |55. After a suitable interval of time, air is admitted to the motor |68 which rocks the bell crank |64 in a clockwise direction as seen in Fig. 4 to set the clamp |56. The clamp |56 holds the bag during the opening, shaping and lling operation and, when lling is complete, the valve mechanism in valve box 36 allows the air in motor |66 to exhaust and spring |12 releases the clamp |56. Since the force of temporary holding rollers |55 is insuiicient to hold a filled bag, the same will drop from the holding device to the conveyor I5.

The bag opening and shaping means. comprising the opening iingers 54, 55, 56 and 51 and the operating means therefor, is mounted for vertical movement from a position in which the fingers are collapsed and nested with the spout as shown in Fig. 4, to a positionw-herein the lower tips of the fingers are in a position to square the bottom of a bag 31. supported by the holding devices`|55, |55 as shown in Fig. 6. Tothis end the mounting plate 66 is attached as by cap screws |16 (Fig. 6) and a suitable spacing member |15 to the lower end of a channel |16. The channel |16 serves as a carriage member and may be seen in section in Fig. 9 and in side elevation in Fig. 3. The channel |16 carries a plurality of sets of track rollers |11 on each side thereof as seen in Figs. 3 and 9. The rollers |11 are mounted upon suitable bearings |18 secured to V-shaped supporting blocks |19 which are in turn secured as by screws |66 to the sides of the channel |16. The rollers |11 ride upon a pair of tracks |8| carried respectively by the angles 46 and 45. The tracks |6| may conveniently be square in cross section and may be secured through spaced V blocks |82 and screws |83 to their respective angles 46 and 45. The channel |16 and the bag opening device supported thereby constitute a bag opening carriage which is thus mounted for vertical movement accurately guided by the antifriction rollers |11 and tracks Suitable power actuated means may be provided to effect the vertical movements of the bagopening carriage. It is preferred to use uid pressure actuated power means and in the embodiment shown in the accompanying drawings a double acting air motor of the cylinder and piston type is employed. It will be understood that any suitable mechanical or electrical power means may be employed for this purpose and that the present invention is not limited to the use of an air motor.

In Figs. 1 or 2 the carriage air motor is indicated generally by the reference numeral |84. The motor |84 comprises a lower head |85, shown in detail in Figs. 7 and-8, an upper head |86, shown in detail in Figs. 3 and 5, a cylinder |81,

' a piston |88, shown in detail in Fig. 6, and a pis- `ton rod |89. The piston rod |89 is connected at its upper end to the upper end of the carriage channel |16. As shown in Figs. 2 and 3, the up per end of the piston rod |89 is fitted with an Veye |96 which receives the reduced end oi' a cylindrical stud |9| secured to the upper end of the channel |16. The stud |9| may be formed with a flange |92 and a reduced threaded portion |93 passing through the channel |16 and adapted to receive a nut |94 which serves to secure the stud in proper position.

The piston |88 is secured to the piston rod |86 and comprises upper and lower oppositely disposed exible cups |95 and |96 respectively. The upper portion of the piston |88 has formed thereon a shoulder |91 while the lower portion has a similar shoulder |98. Extending upwardly beyond the shoulder |91 there is a reduced portion terminating in a plunger |99 while a similar plunger 266 'is formed on a reduced portion extending downwardly from the lower shoulder 96. The shoulders and plungers serve purposes which will be hereinafter more clearly brought out. The lower and upper cylinder heads |85 and |86 include the portions 46 and 41 above described which serve the dual purpose o'f securing the cylinder heads to the angles 44 and 45 and oi spacing the angles 44 and 45. The lower head and upper head |86 are provided with seats 26| and 262 respectively (Figs. 8 and3) adapted to receive the opposite ends of the cylinder |81. The heads land cylinder are held in assembled relation by a suitable number oi' elongated bolts 265 extending through the heads and adapted to draw the heads toward one another into firm seating engagement with the ends of the cylinder |61. The upper head |86 is formed with an extension 264 (Fig. 3) through which the piston rod |89 may extend. A packing nut 265 `having suitable packing material 266 therein is threaded upon the extension 264 and serves to prevent escape of air around the piston rod |89. The double-ended piston |88 divides the air motor into lowen and upper chambers having separate cylinder heads through which air may be supplied and exhausted.

Except for the packing gland 264, 265, 266l above described and minor details to be hereinafter described the cylinder heads |65 and |86 constitute a complementary pair and a detailed description of one of these heads will suffice. Referring now to Figs. 6, '1 and 8, it will be seen that the head comprises two separate parts, a lower part 261 and an upper part 268. This particular construction is adopted in order to simplify casting, machining, and assembling of the head. The upper part 268 has extending completely therethrough an opening concentric with the cylinder seat 26| and a bushing 269 is positioned in this opening. The internal diameter of the bushing 269 is such as to snugly receivev the plunger 266 of the piston |88 and is extended beyond the head part 268 to cooperate with the shoulder |98 of the piston |88 to establish a denite stop or final position of the piston relative to the cylinder |65. Thelower part 261 has formed therein a recess 2|6 which opens into the bushing 269 and which through a slot 2|I,

vrecess 2|2 and passageway 2|3 communicates with a main air chamber 2|4. The recess 2|6 serves as an inlet and exhaust port and the rate of flow therethrough may be controlled by a neefsageway 2|3 and chamber 2|4 and which may be locked in air-tight adjusted position by a lock nut 2|6 adapted-to bear upon a packing washer y The portion of the upper part 208 which lies within the cylinder |81 but outside oi?- the bushing 209 has formed therein an inlet and exhaust port 2|8 communicating with amating recess l the port 2 |8 is formed there is also formed a pair of inlet ports 222 communicating througha-slot 223 in the upper part 208 and an opening 224 formed in the lower part 201 with the main air chamber 2|4. A ball checl valve 225 is mounted in the upper part 206 and is urged by its spring 226 to seat in the opening 224 to prevent exhaust of the cylinder through the ports 222.

ing a prime and corresponding to the numerals A,

applied to corresponding parts of the lower head |85. The inlet and exhaust port 2|0' differs in dimensions and design from the port 2|0 of head |85 to compensate for the passage of the piston rod |89 therethrough. The main air chamber 2|4' of the upper head is connected by a fitting 221 and the tube 220 to the valve box 30.

The valve mechanism in box 30 is arranged to alternate the inlet and exhaust of each of heads v|85 and |86 and further lto alternate the cycles of inlet and exhaust between the two heads.

Thus, either the lower or upper-cylinder chamber may have uid pressure admitted thereto whilethe other chamber is allowed to exhaust whereby the piston |88 is caused to move upwardly or downwardly within the cylinder |81.

The cylinder heads |85 and '|86 above described -are designed to produce a uniform, rapidstroke b'all check valve preventsl exhaust through ports 222, the air within the' yexhausting chamber will vbe somewhat compressed and will thus assure a uniform and controlled rate of piston travel. When the plunger 200 enters the bushing. 209, the port 2|0 is closed and the air withinthe main cylinder chamber may exhaust only through the port 2|8. Proper adjustment of the needle valve 22| will restrict the exhaust through port 2|8 and so cushion the end of the stroke as to afford a gentle nal stop between the shoulder |98 and bushing 209. Y

From the above detailed description lit will be apparent that there is provided a particularly desirable carriage moving device. The needle valve adjustments may be availed of to adapt the device for raising and lowering the carriage at optimum speed and with a minimum of shock irrespective of wide variations in fluid pressurel which may beencountered in different plants.

In Figs. 15 to 20 inclusive, there is shown a particular valve arrangement which may conof the piston and to provide a cushioned stop at each end of the travel of the piston. yReferring again to Figs. 6, 7 and 8, the operation of the lower cylinderl head will be described. Air under pressure is admitted from the valve box 30 to the chamber 2|4 and passes through the openings 2|3, 220,and 224 to the ports 2|0, 2|8 and 222 respectively. The air passing through port 2|0 acts directly upon the head of plunger 200 while the air passing through ports 2|8 and 222 acts directly upon the piston -cup |96. Thus, air

under pressure is immediately applied to substantially the entire area of the p-iston.|88 to effect rapid movement thereof. When the plunger 200 leaves bushing 209, the lower cylinder chamber is supplied with air emerging from all of the ports 2|0, 2|8 and 222 and the stroke of the piston continues. During this time, the upper cylinder headl86 is exhausting and will provide a cushioned stop for the end vof the piston stroke. identical with that of the lower head the exhausting operation will be explained in connection with the `more detailed showing -of the lower head.

It will be understo that exhausting of the lower head |85 will oc ur when pressure is supward'movement of the piston |88 as from the Since'the action of the upper head is veniently be used to control the fluid pressure motors of the bag opening device abovedescribed. It will be understood that any valve arrangement suitable for the purpose may be used and that the following detailed description is for illustrative purposes only. As shown in Fgs..15 and 16, the tubes |06, |1|, 228 and 228' lead from their respective air motors to a valvel seat 229'forming a part of the valve box 30. A,s shown in Fig. 20 and in Figs. 17, 18 and 19, the valve seat 229 hasv formed therein suitable passageways and recesses for cooperation -with the ports of valves seated thereon. A passageway 230 is formed in the valve seat 229 .and constitutes the main passageway through which a -fluid pressure medium is supplied to the valves. As shown in Fig. 20, the

'passageway 230 is open at one end to receive a 'suitable tting or pipe 230 connected with an air compressor or other suitable source of fluid pressure not shown.

'Fig 1'1 is a sectional view of a valve 23|, actuating mechanism therefor and the valve seat 229,

vshowing an arrangement suitable for control of the bag clamp motor |68. The valveA 23| com-l prises a body mounted upon the valve seat 229 and which has suitable chambers therein andopenings between the chambers controlled by pcppets tings 231 to the valve seat 229. Referring back to Fig. 11, it will be `Aseen that the motor |68 is thus connected by a passageway 238 in the valve seat and an outlet valve port 239 with a. valve chamber 240. A valve chamber 24| opens through an exhaust valve port 242, recess 243 and exhaust opening 244 to, the atmosphere. The lpoppet 232 is urged to closed position by an expansion spring 245 extending bstween a packing washer246 and a tappet 241. The poppet 233 is similarly urged to closed position and is provided with a tappet 248. The tappets 241 and 248 may be alternately position shown in Fig. 3 to vthat shown in Figs. 6

or 8. During the major portion of the stroke, the air within the lower cylinder chamber Aexhausts through ports 2|0 and 2|8. Since the y depressed to open the valves 232 and 233 by a rocker/249 pivot-ed at 250 upon the valve body.

:The rockcr'is urged by a spring.25|, superior to the spring 245, to rock in a clockwise direction',

as seen in 17, whereby the poppe-t valve 232 is normally maintained in an open position. The spring 25| is fastened at one end to the upper arm of-rocker 249 and at its other end the spring is anchored as to a pin 252 lying outside the valve seat 229. The lower arm of the rocker 249 is provided with an antifriction roller 253 which is adapted to cooperate with a suitable cam mechanism to rock the rocker 249 in a counterclockwise direction whereby the poppet 232 is allowed to close and the poppet 233 is opened.

In the position illustrated in Fig. 17 the poppet 232 is closed and the uid pressure supply from passageway 230 is closed'o within chamber 236. Poppet 233 is open to allow the motor |68 to exhaust through chambers 240 and 24| and exhaust opening 244 to the atmosphere. In the position thus illustrated the bag clamp |56 (Fig. 2) s in open position corresponding to the position of parts illustrated in Figs. 1, 2 and 4. When the cam mechanism allows spring 25| to rock the rocker 249 to open poppet 232 and close poppet 233 the fluid pressure medium iiows from passageway 230 through chambers 236 and 240, outlet port 239, ete., to lthe motor |68 whereby theclamp |56 is moved to clamping position illustrated in Fig. 6.

A valve 254, identical with valve 23| above described, may be provided for control of the motors |I and |02 which effect expansion and contraction of the bag-opening ngers. As -shown in Figs. and 20 the valve 254 is seated upon the valve seat 229 and.is provided with an inlet port 255 communicating with supply passageway 230, an exhaust port 256 and an outlet port 251 connected by a fitting 258 with tube |06 leading to the motors lili and |02. The valve 254 is `urged by spring 259 into an exhaust position as described above in connection with valve 23| whereby the bag described. -The valve 260 is provided withfour are similar in all respects with the poppets described above in connection with Fig. 17. In the valve position illustrated in Figs. 18 and 19, the upper poppets 284 and 285 are held open by the action of a spring 288 upon the upper arm of a. rocker 289 bridging the tappets. The valve may be reversed by cam mechanism acting upon an antifriction roller 290 carried by the lower arm of rocker 289.

In the valve position illustrated in Figs. 18 and 19 a fluid pressure medium from supply passageway 230 enters the chamber 263 (Fig. 19) passes through the open 'poppet 284 to outlet chamber 266 and thus to the lower cylinder head |85 to produce an upward movement of the bagopening carriage. Pressure medium exhausted from the upper cylinder head |86 passes through outlet port 212 (Figj 18) into chamber 21| through open poppet 285 into the exhaust chamber 216 and passage 211 (Fig. 18) to chamber 218 and 219 (Fig. 19). through 219 (Fig, 18)

into passageway 280 andV exhaust port 28| and ports Vand four poppets. Fig. 18 is a section in the plane of one pair of ports and poppets while Fig. 19 is a section in the plane of the other pair of ports and puppets. In Fig. 19 there is shown an inlet port 26| communicating through 'a recess 262 with the supply passageway 230 and openingA into aninlet chamber 263 in the valve body. The

chamber 263 projects forwardly from the plane of Fig. 19 through a passageway 264 into the plane of Fig. 18 and into an inlet chamber 265.

In the plane of Fig. 19 the valve 260 is provided with an outlet chamber 266 and outlet port 261` communicating through a recess 268, passageway 269 and a fitting 210 with the tube 228 (Fig. 16) leading tothe lower cylinder head |85.

In the plane ofFig. 18 the valve 260 is provided with an outlet chamber 21| and outlet port 212 communicating through a recess 213, passageway 214 and a tting 215 with the tube 228' leading to the upper cylinder'head |86.

In the plane of Fig. 18 the valve 260 is provided with an exhaust chamber 216 which extends through a passageway 211 rearwardly from'the plane of Fig. 18 into the 'plane of Fig. 19 and into an exhaust chamber 218. The chamber 218 has a portion 2-19 which extends forwardly into the plane of Fig. v18. As shownin Fig.- 18 theportion 219 communicates through a passageway 280 with an exhaust port 28| which opens through a recess 282 and exhaust opening 283 to the atmosphere.

The valve 260 isprovided with upper poppets Vsuch as set screws (not shown).

thus to the atmosphere.

When the valve 260 is reversed, pressure medium flows from supply passageway 289 to chamber 268 (Fig. 19) through passageway 264 into chamber 265 (Fig. 18) through the now open poppet 281 into outlet chamber 21| and through port 212 to the upper cylinder head |86 to pro duce a downward movement of the bag-opening carriage. Pressure medium exhausted from the lower cylinder head |85 passes through outlet port 261 (Fig. 19) into chamber 266 and through the now open poppet 286 into exhaust charnber 218, 219 and thus through port 28| (Fig, 18) to the atmosphere.

As shown in Fig. 15, the valves 23|, 254 and 268 may be mounted upon the valve seat 229 in proper alignment for operation by a set of individually adjustable cams carried by the cam shaft 29. The shaft 29 is rotatably carried in bearings 29| and 292 secured to the valve box 30 and is rotated by the motor I8 as described above in connection with Fig. 1.

The cam provided for operation of the bag clamp valve 23| may comprise two relatively adjustable segments 293 and 283 (Figs. 15 and 17) secured to hubs 294 and 294'. 'I'he hubs 294 and 294' may be fixed in adjusted angular relation to the shaft 29 by any suitable means The segments 2.93 and 293 may be further secured in adjusted position relative to'one another as by a clamp bolt 295 passing through arcuate slots 296 and 296 formed respectively in the segments 293 and The cam provided for operation of the bag- 284 (Fig. 19) and 285 (Fig. 18) and lower poppets and 291' (Figs. 15 and 17) mounted as are the segments 293 and 293' upon the shaft 29. Arcuate slots 288 and 298 and a clamp bolt 299 are provided to assist in securing the segments in adjusted relationship.

The cam provided for operation of the carriage valve 260 comprises relatively adjustable segments 300 and 300' (shown in Figs 15 and 18 and omitted from Fig ,17 for purposes of clarity)` mounted as are' the segments 293 and 293 upon th haft 29.` Arcuate slots 30| and 30| and a clam bolt 302 are provided to assist in securing ents in adjusted relationship.

Th valve positions in Figs. 15, 17, 18 and 19.

cor espond to the :machine position illustrated in Figs. 1, 2,y 3 and 4 in which the carriage is up.

the bag and increase the cyclic rate of operation.

fingers 55--51 are collapsed and the clamp |56 is open. It will be assumed that an empty bag 31 has been positioned beneath temporary holding rollers |55 as shown for example in Fig. 4.

, Accordingly, the cam 293, 293is positioned to hold the valve 23| -in the position shown in Fig. 1'7 and the cam 291, 291' is positioned to hold the valve 254 in the position shown in Fig. 17. The cam 300, 300 is positioned away from follower 290 wherebythe valve 280 is held in the position illustrated in Fig. 18 by the spring 288. The cams 293, 291, 300 are adjusted relatively to one another upon the shaft 29 in order to operate their respective valves in proper timed relation and the individual segments of v'these cams are adjusted to vary the duration of operation of each valve.A A preferred adjustment of the cams is illustrated in Figs. l'1 and' 418 of the drawings and the resultant sequence of machine operations will now be described.

The shaft 29 is rotated in a clockwise direc When an automatic bag-positioning device is used in connection with the device of the present disclosure, it'would perhaps be possible to shortenv that portion of the cycle assigned to bag positioning and lengthen the time available for opening and filling whereby the cyclic rate of operation could be materially increased. Y

While the individual adjustments of cams 293, 291 and 300 are relative to the shaft 29 and are,

therefore, relative to sprocket 3|, it will be aption as indicated by the arrows and the cam segment 293' will be withdrawn from follower 253 allowing the spring to reverse valve 23|. The reversal of valve 23| operates as above described to set the bag clamp |55. Continued rotation of shaft 29 will project the cam segment 300' into contact with the follower 296 and result in reversal'of the carriage valve 259. The reversal of valve- 260 operates as above described to start the downward movement of the bag-opening carriage. Continued rotation of shaft 29 will withdraw the cam segment 291' from its follower and result in reversal of the finger controlling valve 255 which operates as above described to cause expansion of the bag-opening fingers 5d-51- parent that by adjustment of the sprocket 3| relative to the. shaft 29 the timing of the filling device may be conveniently varied without disturbance of the cams.

The operation of the bag-opening device will now be described in connection with the opening of a square bag. Referring now to Figs. 21 and 25, it will be seen that a square bag 31 has been partially opened, placed over the lower ends of the fingers 5d-51 and positioned beneath the rollers |55. The lower portion of the bag body tapers to a bottom fold or crease 303 formed during manufacture and a rectangular bottom may be defined therein by score lines 305 and 305 formed in the front and rear walls and in the gusseted side walls respectively. As explained f above in the description of' the cyclic operation 'of the device, the clamp |55 is set and the col- Preferably, the cams 300' and 29l' are so timed that the fingers 54-51 are fully expanded shortly before the downward movement of the carriage is complete. When the carriage reaches its lowermost position and the fingers are fully expanded a charge of material is dumped from one of the weighing devices 35 (Fig. l) under timed control of the cam shaft 34. The material starts to fiow through hopper and spout 5| into the now fully .opened and shaped bag 31.v While the filling operation proceeds the cam segment 291 is approaching its follower and when filling is well` started the 'segment 291 reverses the valve 254 to collapse the fingers 55-51. Shortly thereafter the segment 300 is withdrawn from the follower 290, whereby the valve 260is' reversed to start the upward travel of the carriage. The filling operation continues while the carriage is returned to its uppermost position and continues thereafter until completed. Upon completion of the filling operation the segment 293 contacts the follower 253, reverses valve 23| and thus releases the bag clamp |55. The segments 293, 293' are so adjusted as to provide a sufficient period of time for the filled bag to ,drop upon conveyor l5 and to allow the operator of the machine toposition an empty'bag for the initiation of a new cycle of operation identical with that just described.

It will be readily apparent that the cams 293, 291 and 300 may be variously adjusted and timed to compensate for variations in the time req'uired for flow of material from the weighing devices to the bag as well as to compensate for varying-degrees of skill in the placement of empty bags in position where manual operation is contemplated. Thus, when a freely .owing material is to-be packaged it may be possible to shorten the -portion ofthe lcycle assigned to the filling operation, lengthen the portion assigned to positioning of lapsed ngers 513-51 start their downward movement. While the fingers may remain collapsed until downward travel is complete and be thereafter expanded to bag-opening position, it is preferred to'overlap these operations.- Accordingly, from a position in the general vicinity of that illustrated in Figs. 22 and 26, the further downward movement of the fingers 15d-5i maybe a'c-h companied by rocking thereof 'about the pivots 33.35211 and 12.

The length of fingers 54-57 and the extent of vertical movement thereof are so proportioned with regard to the particular bag to be opened that in their lowermost .position the lower tips of the fingers lie within a plane substantially coincident with the plane of score lines 303, 395, or, stated otherwise, in a position wherein only sufficient bag material lies beyond the ends of the fingers to provide a rectangular bottom of dimensions substantially equal to the rectangular dimensions of the bag body when fully exlpanded or opened. Thus, while the following score lines.

description is made in connection with a bag provided with score lines 303 and 305, it will be understood that the operation of the fingers is in no way dependent upon the provision of such 'I'he fingers are preferably formed with substantially right angular outer corners and the extent of their lexpansive movement is preferably so limited that in their fully expanded position the lower tips thereof define a rectangle substantially congruent with the rectangular bag bottom defined by score lines 304 and 305. Thus,

in the movement of the fingers from the position 7`5 Figs. 6 and 11.- In thisfconnection, it `may be in Figs. 22 and 26 to the position in Figs. 23, 27

and 24 the corners of the .bag bottom will be v positively moved away from each other in paths which are resultantly diagonal and the score lines 304, 305 will be positively moved to posins wherein they establish a rectangular bottom of desired dimensions.

Th fold or crease 303 will be flattened Out and draw upwarmy substantiauy into the plane or l sco lines 304 and 305. Detailed sectional views of the opened andsquared bag are presented in 

